Bytecode is a term used to describe a form of instruction set that is processed by a software interpreter, typically a virtual machine like the Java Virtual Machine (JVM). It serves as an intermediate representation of the source code, which is written in a high-level language. Bytecode is not directly understandable by the CPU; instead, it consists of compact numeric codes, constants, and references that are the result of the compiler's parsing and semantic analysis of the source code.

Bytecode Generation and Execution

When a high-level language program is compiled, the compiler converts the source code into bytecode. This bytecode is then either interpreted directly by a virtual machine or further compiled into machine code for execution, which can improve performance significantly. The use of bytecode makes Java and other languages platform-independent, as the same bytecode can run on different operating systems and devices, provided a compatible virtual machine is available.